Securing The One: Canada’s tallest building

A Bauer BG 55 was recruited to build the more than $1 billion Toronto development

When construction is complete, The One will become Canada’s tallest building, and second only to the CN Tower as the nation’s tallest man-made structure.

Located at Yonge Street and Bloor Street West in Toronto, The One will reach 306 metres tall and feature 85 storeys. The cost of building The One has been pegged at more than $1 billion, with construction wrapping up in 2022.

“If you’re lucky, you get one opportunity in life to contribute to a project like The One,” said Sam Mizrahi of Mizrahi Developments, the company behind The One. “Yonge and Bloor is one of the most iconic intersections in the city and arguably the country. Mizrahi Developments has a responsibility to deliver something Canada hasn’t seen before and we’re grateful and excited to get started.”

Located on the border of Toronto’s downtown and Yorkville neighbourhood, The One was designed to serve as a transition between the two urban areas. Inspired by both neighbourhoods’ characteristics, The One will bridge the upscale neighbourhood quality of Yorkville, the commercial boulevard of Bloor Street and the local heritage character of Yonge Street.

“The One is the final piece of the jigsaw in the tower cluster at the Yonge and Bloor node – one of the most prominent intersections in the city,” said Giles Robinson, a senior partner at Foster + Partners, the architectural firm that designed The One. “The project creates a new anchor for high-end retail along Bloor Street West, while respecting the urban scale of Yonge Street.”

Vertical retail

Inside, The One combines a condominium tower with a retail base, which is integrated with the city’s underground pedestrian PATH network. A pioneer of a new model of vertical retail in the city, the base of The One comprises of nine levels of shops, cafes and restaurants, arranged around a 60-metre atrium. An ‘urban room’ is elevated two storeys above the street, protected from the weather and accessed by two express escalators.

The condominiums are reached via a glass bridge at level 12, and incorporate winter-gardens with panoramic city views.

The building also houses 200 hotel rooms spanning 10 storeys of the building.

Despite the building’s height, it will feature 416 units, to pay homage to its host city’s area code. As well, the tower is topped by a series of duplex penthouses.

In contrast to the typical glass residential towers, the building’s facade features a distinctive bronze exoskeleton frame, which transforms as the tower rises to articulate the change in function.

With the exoskeleton exterior, and trusses of bronze metallic material, the interiors are able to incorporate wide glass expanses. In fact, unlike any other building in Canada, The One will feature corners where two sheets of glass meet, to provide panoramic views of Toronto’s landscape.

“The One will set new standards for commercial and retail developments in Canada. We’re extremely excited to be working with Mizrahi to realize this fantastic vision, and look forward to the next stages of the project with great anticipation,” Robinson said.

Building The One

Construction of The One began in October of 2017. GFL Infrastructure – Shoring & Foundations is kelly drilling 1,180 mm diameter secant piles for the shoring wall to allow for the deep excavation for the project. The company purchased a new Bauer BG 55 from ECA Canada Company to complete the task.

“The operator was impressed by the power of the rig and the speed of the main winch,” said Ray Kemppainen, branch manager of ECA Canada.

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The piles are drilled up to a depth of 40 metres through various soil conditions including clay and a layer of limestone above the shale layer at the bottom of the boreholes.

As well, Bauer sectional temporary casings are being used to a depth of up to 37 metres to stabilize the boreholes. The BG 55, with its rotary torque of 553 kNm and crowd system effective push/pull force of 460/590 kN (530/680 kN nominal), is also being used to install and remove the casing.

“As the second largest and powerful drill rig that Bauer offers, the BG 55 can tackle these large types of drilling jobs with ease,” Kemppainen said.

The Bauer BG 55 is powered by a Cat C18 engine and includes a single layer main winch to minimize rope wear.

The BG 55 also offers a range of other features, including the vario-crowd winch system on the mast, which enables optimization of the crowd system in particular applications, eliminating the need for the time-consuming disassembly of the crowd ropes during transport.

As well, the machine features a reduction of fuel consumption by up to 30 per cent and significantly reduced noise levels.

In the cab, the BG 55 features an ergonomic space with air-sprung, heated operator seat and high functionality joysticks.

Thanks to the wireless remote control, numerous rigging and derigging functions, such as extending or retracting the undercarriage or travelling with the rig, may be performed outside of the danger zone. The wireless remote control also assists with several service activities, like the operation of the winches during rope changes.

To improve safety, the rig is equipped with guardrails on the upper level; a walking platform with handrail; upward folding service doors; closed circuit cameras for the rear area and main winch surveillance with display on an integrated screen in the operator’s cab; and hydraulic locking of the support trestle.